Does body mass index impact passing voiding trial after midurethral sling procedures for stress urinary incontinence?

Objective: To test the hypothesis that body mass index (BMI) is a factor associated with passing a voiding trial after midurethral sling procedures for stress urinary incontinence (SUI). Study Design: The medical records of 136 consecutive patients who underwent placement of either tension-free vaginal tape (TVT) or transobturator tape (TOT) for SUI during a 1-year period (September 1, 2007 to August 31, 2008) were retrospectively reviewed. Variables assessed were BMI, age, and passing or failing a postoperative urinary voiding trial. Patients with concomitant pelvic organ prolapse surgeries were not included in this analysis. Results: Sixty-seven patients underwent TVT, whereas 69 had TOT procedures. In the TVT group, 30 patients (42%) were unable to void immediately postoperatively compared with 11 patients (16%) in the TOT group (P = 0.0003). The mean (SD) age and BMI of patients who failed or passed voiding trials was 58.6 (12.0) years and 28.0 (4.9) kg/m² or 53.5 (12.3) years and 29.8 (5.7) kg/m², respectively. Of 38 patients who did not pass a voiding trial on the day of the procedure, 31 (82%) passed on postoperative day 1, and all patients had passed a voiding trial by postoperative day 11. The mean (SD) BMI for 7 patients who did not pass voiding trial by postoperative day 1 was 28.3 (5.2) kg/m². Conclusions: Women with higher BMIs were more likely to pass voiding trials after midurethral sling procedures. Patients who had TOT placement had greater success passing a postprocedure voiding trial than did patients who had TVT placement.